The invention relates to timing apparatus, and in particular to timing devices for coin-operated, elapsed time apparatus such as classified in class 194, subclasses 9,16 and 18.
Counting circuits for adding and subtracting digital pulses, such as described in U.S. Pat. No. 2,735,005 to Steele, are well known.
Coin receiving circuits, such as described in U.S. Pat. No. 3,279,480 to Jarvis and U.S. Pat. No. 4,124,110 to Hovorka are likewise well known.
Elapsed time timing devices are well known, and the use of such timers for counting down a purchased period of time, such as taught in U.S. Pat. No. 4,176,739 to Corcoran, are well known.